Download MendeleyHigh-resolution solution structure of the 18 kDa substrate-binding domain of the mammalian chaperone protein Hsc70.
Morshauser, R.C., Hu, W., Wang, H., Pang, Y., Flynn, G.C., Zuiderweg, E.R.(1999) J Mol Biol 289: 1387-1403
- PubMed: 10373374
- DOI: https://doi.org/10.1006/jmbi.1999.2776
- Primary Citation of Related Structures:
1CKR, 7HSC - PubMed Abstract:
The three-dimensional structure for the substrate-binding domain of the mammalian chaperone protein Hsc70 of the 70 kDa heat shock class (HSP70) is presented. This domain includes residues 383-540 (18 kDa) and is necessary for the binding of the chaperone with substrate proteins and peptides. The high-resolution NMR solution structure is based on 4150 experimental distance constraints leading to an average root-mean-square precision of 0.38 A for the backbone atoms and 0.76 A for all atoms in the beta-sandwich sub-domain. The protein is observed to bind residue Leu539 in its hydrophobic substrate-binding groove by intramolecular interaction. The position of a helical latch differs dramatically from what is observed in the crystal and solution structures of the homologous prokaryotic chaperone DnaK. In the Hsc70 structure, the helix lies in a hydrophobic groove and is anchored by a buried salt-bridge. Residues involved in this salt-bridge appear to be important for the allosteric functioning of the protein. A mechanism for interdomain allosteric modulation of substrate-binding is proposed. It involves large-scale movements of the helical domain, redefining the location of the hinge area that enables such motions.
Organizational Affiliation:
Department of Biological Chemistry,University of Michigan, Ann Arbor, 48109, USA.
